JP2003217201A - Turntable of spindle motor and assembling method for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a turntable equipped with a clamping mechanism which is mechanically simple, is robust, features good productivity and has high reliability to retain the clamping capability of a disk without deterioration in spite of an ambient temperature change. <P>SOLUTION: A turntable body 10 is formed of an elastic synthetic resin, such as a polycarbonate resin, and an annular back yoke 20 consisting of a thin metallic sheet of a magnetic material, such as an iron sheet, and an annular magnet 30 are fastened into an annular hole 12 of a center part of the center guide 11. The back yoke 20 is locked by a locking pawl 14 having a spring characteristic disposed at an outer peripheral wall 12b of the annular hole 12 and is fastened to a base surface 12a of the annular hole 12. The magnet 30 is fastened atop the back yoke 20 by an adhesive. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a turntable of a spindle motor which attracts a disk holding clamper.

[0002]

2. Description of the Related Art Conventionally, a media recording / reproducing apparatus using a media disk has a turntable fixed to a shaft of a spindle motor provided in the apparatus, and the media disk is mounted on a disk mounting surface of the turntable. Then, the disk was rotated and information was written or read from this disk. However, since the turntable on which the media disc is placed rotates at high speed, if there is a slight displacement or warp of the center of gravity within the plane of the placed disc, rotation of the disc within that plane will occur due to surface wobbling. There is a problem that the center is deviated, and eventually information is read from the track of the disc or an optical pickup for recording information on the track of the disc is separated from the track.

Therefore, as a method of further increasing the restraining force of the rotating media disk, an annular hole is provided in the center of the turntable, and a magnetic means is provided in the hole.
With this magnetic means, a clamper made of a magnetic material metal thin plate such as an iron plate provided so as to sandwich the mounted media disk is attracted, and the media disk is firmly pressed against the disk mounting surface of the turntable. Was there.

Generally, the turntable is formed of a lightweight synthetic resin because it is necessary to minimize the rotation moment. As the structure of the magnetic means provided in the turntable, an annular magnet is fixed to an annular hole in the center of the turntable (single magnet method).
Alternatively, a back yoke made of a thin metal plate made of a magnetic material such as an iron plate and an annular magnet are fixed (a magnet system with a back yoke) is often used. As a method of this fixing, an annular magnet is directly fixed to the bottom surface of the hole in the central portion of the turntable by using an adhesive, or a back yoke is fixed by using an adhesive and the surface of this back yoke is fixed. An example is a ring-shaped magnet fixed with an adhesive.

[0005]

However, in the above bonding method, since the synthetic resin has a remarkably large linear expansion coefficient as compared with the metal or magnet material, the annular hole of the synthetic resin turntable is formed. If you attach a back yoke made of metal and a magnet equivalent to metal to the bottom surface of the part,
A significant difference in linear expansion coefficient occurs depending on the thermal conditions of the use environment, and there is a problem that the adhesion is forcibly peeled off and the magnet comes off the adhesion part. Further, there is a problem that the bottom surface of the hole portion of the turntable to which the magnet and the back yoke are adhered is distorted due to a change with time, and the adhesion is forcibly peeled off, and the magnet and the back yoke are separated from the adhered portion.

Therefore, the present invention solves the above-mentioned problems and has a simple structure, yet is robust and has good productivity, and has high reliability that does not deteriorate the clamping capacity of the disk against ambient temperature changes. An object of the present invention is to provide a turntable equipped with the disc clamp mechanism.

[0007]

In order to solve the above-mentioned problems, as in the invention described in claim 1, an annular back yoke is provided on the bottom surface of an annular hole formed in the center of the center guide. In a turntable of a spindle motor having an annular magnet or an annular single magnet, the back yoke or the single magnet is fixed to the bottom surface of the hole by a mechanical locking means provided on the peripheral wall of the hole. Can be achieved by

The mechanical locking means is provided on the outer peripheral wall of the hole, as in the invention described in claim 2.
4. The back yoke or the single magnet, which is a locking claw having a spring property for locking the outer peripheral edge of the back yoke or the single magnet, or is provided on the inner peripheral wall as in the invention according to claim 3. An outer peripheral edge of the back yoke or the single magnet provided on the outer peripheral wall of the hole as in the invention according to claim 4, wherein the inner peripheral edge of the back yoke or the single magnet is retained. This can be achieved by providing a locking claw that locks the locking claw and a cutout portion that fits the locking claw on the outer circumference of the back yoke or the single magnet.

Further, as in the invention described in claim 5, a plurality of the mechanical locking means are arranged on the outer peripheral edge of the back yoke so as to project radially outward, and are integrally formed with the back yoke. The formed protruding claw, a vertical groove portion formed in a concave shape so that the protruding claw of the back yoke provided on the outer peripheral wall of the hole portion can be fitted, and the hole from one of the side wall surfaces forming the vertical groove portion Along the bottom surface of the portion, the outer peripheral wall is provided with a lateral groove portion formed by cutting out in a substantially arcuate shape in which the protruding claw is rotatable, and the movement of the protruding claw near the opening of the lateral groove portion is blocked. This can be achieved by using the provided protrusion.

Further, the mechanical locking means may be the same as in claim 6.
According to the invention described in (1) above, a projection portion integrally formed on the surface of the projection claw that is radially outwardly arranged in a plurality of projections on the outer peripheral edge of the back yoke and the outer peripheral wall are provided. A vertical groove portion formed in a concave shape into which the protrusion claw of the back yoke can be fitted, and a protrusion provided with the protrusion portion on the outer peripheral wall from one of the side walls forming the vertical groove portion along the bottom surface of the hole portion. Achieved by providing a lateral groove portion in which the claw is notched in a substantially arcuate shape capable of rotating movement, and a recess or step provided in the vicinity of the opening of the lateral groove portion so as to prevent the projection portion from moving. it can.

According to a seventh aspect of the present invention, in the method of assembling the turntable, a locking claw having a spring property is provided on an outer peripheral wall of an annular hole formed in a central portion of the center guide. An annular back yoke is inserted into the hole, the outer peripheral edge of the back yoke is locked by the locking claw, and an annular magnet is adhered to the upper surface of the back yoke, or an annular single magnet is attached to the hole. This can be accomplished by inserting the magnet and locking the outer peripheral edge of the single magnet with the locking claw.

Alternatively, as another assembling method, as in the invention described in claim 8, a locking claw having a spring property is provided on the inner peripheral wall of an annular hole formed in the center of the center guide, An annular back yoke is inserted into the hole, the inner peripheral edge of the back yoke is locked by the locking claws, the shaft is press-fitted into the boss portion in the center of the center guide, and then the upper surface of the back yoke is looped. Or attach an annular single magnet to the hole, and lock the inner peripheral edge of this single magnet with the locking claw, and attach the shaft to the boss at the center of the center guide. It can be achieved by press fitting.

Alternatively, as another assembling method, a ninth aspect is provided.
According to the invention described in (1), a locking claw is provided on the outer peripheral wall of the annular hole formed in the central portion of the center guide, the annular back yoke is inserted into the hole, and the engaging member is provided on the outer periphery of the back yoke. After inserting the notched part, then rotating this back yoke and locking this outer peripheral edge with the locking claw, either sticking a ring-shaped magnet on the upper surface or ring-shaped the hole. Of the single magnet, the cutout portion provided on the outer periphery of the single magnet is fitted into the locking claw, and then the single magnet is rotated to lock the outer peripheral edge with the locking claw. Can be achieved by

Further, as another assembling method, the method according to claim 1 is adopted.
As in the invention described in 0, the annular groove formed in the central portion of the center guide is provided with the outer peripheral wall, the vertical groove portion, and the protrusion on the groove sidewall surface adjacent to the vertical groove portion adjacent to the vertical groove portion. A horizontal groove portion is formed, and a back yoke having a plurality of protruding claws integrally arranged on the outer peripheral edge is inserted into the hole, and the protruding claw is fitted into the vertical groove portion, and The back yoke is rotated in the direction of the lateral groove, the protruding claw is fitted into the lateral groove, locked by the protrusion provided in the lateral groove, and an annular magnet is bonded to the upper surface of the back yoke. Can be achieved by

Further, as another assembling method, the method according to claim 11 is adopted.
In the outer peripheral wall of the annular hole portion formed in the central portion of the center guide, a vertical groove portion and a recess or a step portion on the groove side wall surface adjacent to the opening portion adjacent to the vertical groove portion are provided. The provided lateral groove is formed, and a plurality of protruding claws integrally arranged on the outer peripheral edge and a back yoke having a protruding portion on the protruding claw surface are inserted into the hole, and the protruding claw is inserted. Is inserted into the vertical groove portion, then the back yoke is rotated in the direction of the horizontal groove portion, the protrusion is inserted into the horizontal groove portion, and the protrusion or the step portion is provided in the horizontal groove portion. Stop,
This can be achieved by bonding an annular magnet to the upper surface of the back yoke.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a turntable showing a first embodiment of the present invention. In addition, in FIG.
It is an expansion perspective view which shows the principal part which concerns on this invention shown in FIG. FIG. 3 is an exploded perspective view showing the assembling procedure of FIG. In FIG. 1, a turntable main body 10 of the turntable is formed of an elastic synthetic resin such as polycarbonate resin, and an annular hole 12 is provided at the center of the center guide 11. Bottom 1
An annular back yoke 20 and an annular magnet 30 made of a magnetic material metal thin plate such as an iron plate are fixed to 2a.

More specifically, the back yoke 20 is locked by a locking claw 14 having a spring property provided on the outer peripheral wall 12b of the annular hole 12 of the center guide 11, and the annular hole of the center guide 11 is locked. It is fixed to the bottom surface 12a of the plate 12. A magnet 30 is fixed to the upper surface of the back yoke 20 with an adhesive.

FIG. 2 is an enlarged perspective view of an essential part showing the structure of the locking claw 14 provided on the outer peripheral wall 12b of the annular hole 12 of the center guide 11 and having a spring property. Figure 2
In this case, the locking claws 14 are integrally formed with the turntable body 10 while the outer peripheral wall 12b forming the center guide 11 is cut at a plurality of locations. Bottom 12
The size of the gap from a to the locking claw 14 is slightly larger than the thickness of the back yoke 20.
The diameter of the envelope formed by the tip of 4 is normally smaller than the outer diameter of the back yoke 20, and is larger than this outer diameter when it is narrowed. Also, this locking claw 1
Since both ends of 4 are connected by a thin strip-shaped connecting portion 14a of the synthetic resin itself forming the turntable body 10, the locking claw 14 can always have a spring property.

FIG. 3 shows an assembly procedure of the turntable shown in FIG. First, the turntable body 10
The back yoke 20 is attached to the central boss 13 of the annular hole 12 of
The hole 21 provided at the center of the is inserted into the bottom surface 12a by pressure, and the outer peripheral edge 22 is locked by the locking claw 14. next,
An adhesive is applied to the upper surface 23 of the back yoke 20 that is locked and fixed to the annular hole 12 of the turntable body 10.

Further, the hole 31 of the magnet 30 is fitted into the boss portion 13 of the turntable body 10 and fixed to the upper surface portion 23 of the back yoke 20 previously fixed. Therefore, since the back yoke 20 is not fixed to the bottom surface 12a of the hole 12 by adhesion, this fixation is not affected by the linear expansion coefficient of the turntable body 10, and the linear expansion coefficient of the magnet 30 is Since the coefficient of linear expansion of the back yoke 20 is approximately equal to that of the back yoke 20, it is possible to prevent the above-described accidental peeling of the adhesive portion due to a temperature change or the like. Also, the adhesive is applied to the annular hole 12 of the turntable body 10 during application.
Since it enters into the gap between the bottom surface 12a and the back yoke 20 locked there, it is possible to further eliminate the assembly play and further improve the strength of the adhesion.

FIG. 4 is a sectional view of a turntable showing a second embodiment of the present invention. Note that FIG. 5 is an exploded perspective view showing an enlarged configuration of a main part according to the present invention shown in FIG. Further, FIG. 6 is a perspective view showing a further enlarged main part in FIG. Further, FIG. 7 is an explanatory view showing the assembly procedure of FIG.

In FIG. 4, the turntable main body 210
Is formed of an elastic molding resin such as polycarbonate resin, and an annular back yoke 220 and an annular magnet 230 made of a magnetic metal thin plate such as an iron plate are fixed to an annular hole 212 at the center of the center guide 211. ing. This back yoke 220 is provided with the center guide 21.
It is locked by a locking claw 214 provided on the inner peripheral wall 212c of the one annular hole 212 and has a bottom surface 212a of the annular hole 212 of the center guide 211. A magnet 230 is fixed to the upper surface of the back yoke 220 with an adhesive.

In FIG. 5, the boss portion 213 forming the inner peripheral wall 212c is formed integrally with the turntable body 210 while being cut at a plurality of locations. The size of the gap from the bottom surface 212a to the locking claw 214 is slightly larger than the thickness of the back yoke 220, and
The diameter of the envelope formed by the tip of the locking claw 214 is normally larger than the diameter of the hole 221 of the back yoke 220.
When it is narrowed, it is formed so as to have a diameter smaller than this.

FIG. 6 is a perspective view showing the locking claw 214. In FIG. 6, since both ends of the locking claw 214 are connected by the belt-shaped connecting portion 214a of the resin itself, the locking claw 214 can have a spring property.

FIG. 7 shows an assembly procedure of the turntable shown in FIG. First, as shown by the arrow in FIG. 7A, the back yoke 220 is inserted into the annular hole 212 formed in the center of the center guide 211 of the turntable body 210.
Insert the back yoke 22 as shown in Fig. 7 (B).
The inner peripheral surface of the hole 221 of 0 hits the tip of the locking claw 214,
The locking claw 214 is forced to be bent in a dogleg shape in the axial direction. Further, as shown in FIG. 7C, the back yoke 2
When 20 is pushed down, the hole 221 of the back yoke 220 passes through the tip of the locking claw 214, comes into pressure contact with the bottom surface 212a, and locks the peripheral edge of the hole 221 of the back yoke 220 with the locking claw 214.

Next, as shown in FIG. 7D, the shaft 60 is attached to the boss portion 213 formed in the center of the center guide 211.
Is inserted in the direction of the arrow and is press-fitted to a predetermined position (dotted line display portion), the locking claw 214 engages the hole 221 of the back yoke 220.
By being firmly sandwiched between the peripheral edge of the and the shaft 60,
Since the locking claw 214 is fixed to the original position, the back yoke 220 does not come off from the locking claw 214 and the bottom surface 21 of the annular hole portion 212a of the turntable body 211 is fixed.
It is firmly fixed to 2a.

Further, an adhesive is applied to the upper surface portion 223 of the back yoke 220 locked as shown in FIG. 7, and the hole 231 of the magnet 230 shown in FIG. 5 is attached to the boss portion 213 of the turntable portion 211. Insert, glue and fix. Therefore, the fixation of the back yoke 220 is not affected by the linear expansion coefficient of the turntable body 210,
Further, the linear expansion coefficient of the magnet 230 is equal to that of the back yoke 2.
Since the coefficient of linear expansion is almost equal to 20, it is possible to prevent the above-described accidental peeling of the adhesive portion due to a temperature change or the like. Also, the adhesive is applied to the hole portion 2 of the turntable 210 during application.
Since the gap between 12 and the back yoke 220 locked thereto is eliminated, it is possible to eliminate the looseness of the assembly and further improve the bonding strength.

FIG. 8 is a sectional view of a turntable showing a third embodiment of the present invention. Note that FIG. 9 is an exploded perspective view showing a main part according to the present invention shown in FIG. 8. Also,
FIG. 10 is an exploded perspective view showing the assembly procedure of FIG. Figure 8
3, the turntable body 310 is formed of an elastic synthetic resin such as polycarbonate resin, and the center guide 311 thereof has a central hole portion 312 in which an annular back yoke 320 and an annular magnet 330 are formed of a thin metal plate of a magnetic material such as an iron plate. Is stuck.

The back yoke 320 is locked by locking claws 314 fixed to the outer peripheral wall 312b of the hole 312 of the center guide 311 of the turntable body 310, and the bottom surface of the hole 312 in the center of the center guide 311. 312a
Is stuck to. A magnet 330 is fixed to the upper surface of the back yoke 320 with an adhesive.

The hole 3 of the turntable body 310
9 shows the structure of the locking claw 314 fixed to the outer peripheral wall 312b of FIG. 12, the structure of the back yoke 320, and the magnet 330.
Shown in. In FIG. 9, the locking claw 314 is an outer peripheral wall 312b.
A plurality of them are fixed on the surface, and each is integrally formed with the turntable 310. The size of the gap from the bottom surface 312a to the locking claw 314 is equal to the thickness of the back yoke 320, and the diameter of the envelope formed by the tip of the locking claw 314 is the outer diameter of the back yoke 320. Greater,
Further, it is formed to be smaller than the diameter of the hole portion 312 of the turntable body 310.

On the other hand, the back yoke 320 is provided at its outer peripheral edge 322 with a notch portion 324 which is fitted into the locking claw 314 of the hole portion 312 of the turntable body 310.
Further, a central hole 321 that is fitted into the boss portion 313 of the turntable body 310 and a hole 325 for inserting an assembly jig in the middle of the annular surface are provided in the center thereof. The outer diameter of the magnet 330 is smaller than the diameter of the envelope formed by the tip of the locking claw 314 of the turntable body 310, and
A hole 321 that fits into the boss portion 313 of the turntable body 310 is provided at the center.

Next, the assembly procedure of FIG. 8 will be described with reference to FIGS. 9 and 10. First, the annular hole 3 formed in the center of the center guide 311 of the turntable body 310.
Insert the back yoke 320 into the
The notch portion 324 of 0 is fitted into the locking claw 314 of the turntable body 310, and is pressed against the bottom surface 312 a of the hole portion 312.

Next, as shown in FIG. 10, the back yoke 3
An assembly jig (not shown) is inserted into the small hole 325 of 20 and the back yoke 320 is rotated in the direction of arrow A,
The notch 324 is moved from the fitting position of the locking claw 314 (the position of the dotted line 324a), and the outer peripheral edge 322 is moved to the locking claw 31.
Lock with 4. Next, an adhesive is applied to the upper surface portion 323 of the locked back yoke 320, and the hole 331 of the magnet 330 is fitted into and fixed to the hole portion 312. At this time, the rotation of the back yoke 310 by the assembly jig may be in the direction opposite to the illustrated arrow.

Thus, the back yoke 320 is locked by
Outer peripheral wall 312 of hole 312 of turntable body 310
It will be done with a plurality of locking claws 314 fixed to b.
The back yoke 320 is firmly fixed to the bottom surface 312a of the hole 312 of the turntable body 310.
As a result, the fixation of the back yoke 320 is not affected by the linear expansion coefficient of the turntable body 310, and the linear expansion coefficient of the magnet 330 is substantially equal to the linear expansion coefficient of the back yoke 320. The above-mentioned accident of peeling of the adhesive portion due to the above does not occur. Also,
When the adhesive is applied, the hole 3 of the turntable body 310 is applied.
Bottom surface 312a of 12 and the back yoke 3 locked there
Since it enters the gap of 10, the looseness of the assembly can be eliminated and the bonding strength can be further improved.

In the above description of the embodiment of the present invention, the back yoke is used in combination with the magnet for the clamper corresponding to the thinness of the spindle motor including the turntable which is required for the thinner media recording / reproducing apparatus. The structure has been described. However, as a modification of each of the above-described embodiments, in the case of a configuration including only an annular magnet that does not use a back yoke (called a single magnet), there is no need to make the motor thin, and the back yoke is It may be assembled by replacing the single magnets, and these single magnets may be directly locked and fixed by the locking means according to the present invention in each of the above-described embodiments. In this case, the step of bonding the magnet to the back yoke can be omitted.

In the modification of the above embodiment, since the magnet is directly locked by the locking claw provided on the peripheral wall of the central hole of the turntable, the fixing by the adhesive can be completely abolished. As a result, the productivity is further improved, and the fixed magnet can be easily removed, so that the molding resin and the magnet can be easily recycled and sufficient consideration can be given to resources and the environment.

FIG. 11 is a plan view showing a main part of a turntable according to the fourth embodiment of the present invention. In FIG. 11, an annular hole 412 is formed in the center of the center guide 411 of the turntable body 410 made of a synthetic resin having elasticity such as polycarbonate resin.
An annular back yoke 420 made of a magnetic material thin metal plate such as an iron plate is mounted on the bottom surface 412a of the hole 412.

More specifically, at the center of the center guide 411, a boss portion 413 formed by the inner peripheral wall 412c of the hole portion 412 and a through hole 413a are formed at the center thereof. In addition, the inner surface of the center guide 411 formed by the outer peripheral wall 412b of the hole portion 412 is vertically recessed to a position of the bottom surface 412a, and a plurality of vertical groove portions 414 are evenly arranged. Further, the inner surface of the center guide 411 is set to the bottom surface 41 from the one vertical groove side wall surface 414a of the vertical groove portion 414.
A notched lateral groove portion 415 is formed laterally in a circular arc concave shape (shown by a broken line) along 2a.

FIG. 12 is a perspective view showing in detail the surrounding structure of the locking means having the vertical groove portion 414 and the horizontal groove portion 415 shown in FIG. In FIG. 12, the vertical groove portion 414
Forms a concave groove with vertical groove side wall surfaces 414a and 414b and a vertical groove peripheral surface 414c which are substantially perpendicular to the bottom surface 412a of the annular hole 412. In addition, the vertical groove bottom surface 414 of the vertical groove portion 414.
The surface of d is on the same surface as the bottom surface 412a. Further, from the vertical groove side wall surface 414a to the outer peripheral wall 4 of the annular hole 412.
12b, that is, the inside of the center guide 411 is cut out in an arc shape along substantially parallel to the bottom surface 412a to form a lateral groove portion 415.

More specifically, regarding the lateral groove portion 415, since the outer peripheral wall 412b is cut out in an arc shape from the vertical groove side wall surface 414a side, the lateral groove side wall surface 415a and the lateral groove peripheral surface 415 are formed.
c and the lateral groove wall surface 415d. Also,
The lateral groove circumferential surface 415c is formed substantially on the same plane as the vertical groove circumferential surface 414c. In addition, the lateral groove portion 41 formed in this way
The side facing the lateral groove side wall surface 415 a of No. 5 is the lateral groove portion 415.
Since the square pin provided on the core side of the molding die enters so as to have the notch shape, a square hole portion 415e similar to the lateral groove side wall surface 415a is formed to be a cavity. However, the main body of the back yoke 420 is always the bottom surface 412.
Since it is supported on the surface of a, this bottom surface 412 is functionally
It can be regarded that a is the lateral groove side wall surface of the lateral groove portion 415 facing the lateral groove side wall surface 415a.

The vertical groove side wall surface 4 of the lateral groove side wall surface 415a.
A protrusion 416 is provided near the opening on the side of 14a. The protrusion 416 may be attached separately, but it is efficient to form the protrusion 416 integrally with the lateral groove side wall surface 415a during the molding process using a molding die.

FIG. 13 shows the back yoke 4 in FIG.
It is a perspective view which shows the structure of 20 further in detail. In FIG. 13, the back yoke 420 has a hole 4 formed in the center.
21 and the outer peripheral edge 422 form an annular portion 423 as a main body. The diameter of this hole 421 is larger than the diameter of the boss 413 of the turntable 410 in FIG. 11, and the diameter of the outer peripheral edge 422 is smaller than the diameter of the outer peripheral wall 412b.

A plurality of outwardly projecting locking claws 424 are evenly arranged on the outer peripheral edge 422. The size of the locking claw 424 is such that it can be fitted into the vertical groove portion 414 of FIG. 11, and the arrangement angle and the number of arrangement are the same as those in FIG.
The angle of arrangement of the vertical groove portion 414 shown in FIG. In addition, if the arrangement angles are equal, one may be formed and provided at a position of at least about 180 °.

The thickness of the locking claw 424 is smaller than the groove width formed by the annular bottom surface 412a and the lateral groove side wall surface 415a, and larger than the distance between the annular bottom surface 412a and the tip of the protrusion 416. Has been done. In addition, on the same circumference of the annular portion 423, a plurality of holes 4 used for locking work are provided.
25 are evenly arranged at equiangular positions.

FIG. 14 is a plan view showing a state in which the locking work according to the present invention has been executed from the state of FIG. 14
, As shown in FIG. 11, the center guide 411
Back yoke 42 placed in the annular hole 412 of the
0 is rotated about the boss portion 413 in the direction of arrow B to move the locking claw 424 into the lateral groove 415, and the locking claw 424 is locked by the lateral groove inner wall surface 415d and the projection 416. .

The vertical groove portion 414, the horizontal groove portion 415 and the back yoke 42 shown in FIG. 14 will be described with reference to FIGS.
The locked state of the 0 locking claw 424 will be described in detail. FIG. 15 is an enlarged cross-sectional view taken along the line CC of FIG. FIG. 16 is an explanatory view showing a jig used for the locking work.

In FIG. 15, 424a is a vertical groove portion 41.
Back yoke 420 mounted on the bottom surface 414d of the vertical groove 4 of FIG.
The reference numeral 424b denotes a locking claw obtained by rotating the back yoke 420 to the direction of the lateral groove inner wall surface 415d of the lateral groove portion 415 (direction of arrow D).
According to this, the moved locking claw 424b is
At a position of the bottom surface 412a in the position 5, the projection 416 is passed and it is located immediately before the lateral groove wall surface 415d.

The lateral groove side wall surface 415a provided with the projection 416 is the center guide 41 made of synthetic resin.
1 is formed by cutting out the inside thereof, the portion of the lateral groove side wall surface 415a where the protrusion 416 is provided has elasticity, and the rotary jig E (jig as shown in FIG. If the back yoke 420 is forcibly rotated, the locking claw 424 can lift the protrusion 416 upward and easily pass therethrough, and this part is locked. After the pawl 424 has passed, it can quickly return to its original position. As a result, the locking claw 424 serving as the locking portion of the back yoke 420 is securely locked to the protrusion 416 of the lateral groove 415 forming the locking means of the turntable.

In FIG. 16, 412d is the bottom surface 4
12 shows an annular groove provided in 12a for escaping the tip of the jig E. Further, when the locked back yoke 420 is released from the locking means, it can be easily removed by using the jig E. If the tip of the jig E has a length within the thickness of the back yoke 420, the annular groove 412d
Further, when the jig is made of a magnetic material and a permanent magnet or the like and the back yoke is attracted by a magnetic force, the hole 425 becomes unnecessary and the back yoke can be easily manufactured.

FIG. 17 is an exploded perspective view showing the assembly procedure of the turntable according to the present invention. 17, in the turntable according to the present invention, first, the back yoke 420 is fixed to the annular hole 412 of the turntable body 410 by the above-described locking operation, and then the back yoke 42.
An annular magnet 430 is fixed to the upper surface of 0 with an adhesive or the like.

When assembled in this way, the back yoke 420 is magnetically attracted to the magnet 430 and the back yoke 420 in addition to the adhesive, so that the bonding force is enhanced and the back yoke 420 is more firmly fixed. In addition, when the adhesive is caused to flow around the locked back yoke, it is possible to prevent play and seal the square hole 415e.

FIG. 18 is a sectional view showing a state in which the turntable according to the present invention is assembled to the rotor of the spindle motor. In FIG. 18, the end portion of the shaft 60 is press-fitted into the boss portion 413 of the turntable body 410 to which the back yoke 420 and the magnet 430 are fixed. In addition, a cylindrical rotor yoke 40 is fixed near the outer peripheral edge of the turntable body 410 opposite to the mounting surface of the back yoke 420. Also, this rotor yoke 40
A magnet 50 for driving the motor is fixed to the inside of the.

The description is based on the turntable body 410.
Has described the rotor yoke 40 and the integral structure, but the separated structure of the rotor yoke 40 has the same structure.

Next, a fifth embodiment of the present invention will be described with reference to FIGS. 19 and 20. FIG. 19 shows the fifth embodiment of the present invention.
4 is a perspective view showing a back yoke 520 according to the embodiment of FIG. Further, FIG. 20 is a cross-sectional view showing the main parts of the turntable body 510 according to the fifth embodiment. In addition,
The cross-sectional position shown in FIG. 20 is obtained by cutting the position corresponding to the arrow CC in FIG. The fifth embodiment is basically the same as the fourth embodiment, except that the engaging portions provided on the back yoke 520 and the center guide of the turntable body 510 are different. The shape of the stopping means is different

In FIG. 19, the back yoke 520 is
The concentric center hole 521 and the outer peripheral edge 522 form an annular portion 523 which serves as a main body. A plurality of outwardly projecting claw portions 524 are evenly arranged on the outer peripheral edge 522. Locking projections 526 that project in the same direction are formed in the respective surfaces of the claws 524. The locking protrusion 526 may be attached to the claw 524 as a separate component, but it is efficient to integrally form the claw 524 and the claw 524 during press working.

In FIG. 20, a recess 517 is provided at a substantially central portion of the lateral groove side wall surface 515a of the lateral groove 515.
Further, the groove width dimension formed by the bottom surface 512a and the lateral groove side wall surface 515a is formed to be larger than the thickness dimension of the claw portion 524 and smaller than the thickness dimension including the claw portion 524 and the locking projection 526. Further, the distance dimension formed by the bottom surface 512a and the deepest portion of the recess 517 is formed to be slightly larger than the thickness dimension including the claw portion 524 and the locking projection 526.

Reference numeral 524a denotes the back yoke 520 of FIG. 19 mounted on the bottom surface 514d of the vertical groove of the vertical groove portion 514.
524 shows a claw portion provided with a locking projection 526a of
b and 526b connect the back yoke 520 to the lateral groove portion 5
15 shows the positions of the claws and the locking projections that are rotated (moved in the direction of arrow F) to the direction of the lateral groove wall surface 515d of 15 and moved. According to this, the moved claw portion 524b is on the bottom surface 512a surface in the lateral groove portion 515, and the lateral groove inner wall surface 515d.
Is located immediately before, and the locking projection 526b is fitted in the recess 517.

The lateral groove side wall surface 515a provided with the recess 517 is the same as in the fourth embodiment.
Since the inner side of the center guide 511 is cut out, the portion of the lateral groove side wall surface 515a where the recess 517 is provided has elasticity, and the rotary jig E as shown in FIG. By forcibly rotating the back yoke 520, the locking protrusion 526a can easily fit into the recess 517 by lifting the lateral groove side wall surface 515a upward.

As a result, the back yoke 5 is formed in the recess 517 of the lateral groove 515 forming the locking means of the turntable.
The locking projection 526 serving as the locking portion of 20 is securely locked. Further, the second mode has an advantage that the length of the arc of the lateral groove portion is shortened. It should be noted that the tip clearances and holes relating to the jig can be eliminated as in the fourth embodiment.

FIG. 21 is a sectional view showing a modification of the locking means according to the fifth embodiment of the present invention. The cross-sectional position of the turntable body 610 shown in FIG. 21 is the same as the position shown in FIG. In FIG. 21, a step 618 is provided near the opening of the lateral groove side wall surface 615a of the lateral groove 615 corresponding to the lateral groove 515 of FIG. In this way, the step portion 618 can surely lock the locking projection 524b like the recess 517 of FIG. Moreover, the modification of the fifth embodiment can further shorten the length of the arc of the lateral groove portion.

Although the above-mentioned lateral groove portion can be formed by an undercut type die, the die structure becomes complicated,
Since the shape of the protrusion or the recess provided near the opening of the lateral groove side wall surface can be limited, if the mold structure that does not undercut as described above is used, the structure of the mold can be simplified,
In addition, there is a square hole on one side of the lateral groove side wall surface, but the shape of the protrusion or recess is a hemispherical round or semi-cylindrical locking part and the tip of the square pin of the die that forms the lateral groove. It can be easily obtained by engraving on the surface.

[0062]

As described above, according to the invention described in claim 1, an annular magnet with an annular back yoke or an annular single magnet is formed on the bottom surface of the annular hole formed in the center of the center guide. In the turntable of the spindle motor, the back yoke or the single magnet is fixed to the bottom surface of the hole by mechanical locking means provided on the peripheral wall of the hole to fix the back yoke. Is not affected by the linear expansion coefficient of the turntable body itself, and the linear expansion coefficient of the magnet is almost equal to the linear expansion coefficient of the back yoke. No peeling accidents will occur.

Incidentally, the mechanical locking means is defined in claim 2,
According to the invention described in claims 3 and 4, a spring for locking the outer peripheral edge or the inner peripheral edge of the annular back yoke or the annular single magnet to the outer peripheral wall or the inner peripheral wall of the annular hole. By providing a locking claw that has properties,
It is possible to obtain a product having a simple structure, yet robust and excellent in productivity.

And, the mechanical locking means is characterized in that
According to the invention described in claim 6, a projection claw that is arranged on an outer peripheral edge of the back yoke and is integrally formed with the back yoke, or a projection provided on the projection claw, and an outer peripheral wall of the hole. And a lateral groove formed by cutting out the outer peripheral wall from one of the side wall surfaces that form the vertical groove portion along the bottom surface of the hole in a substantially arcuate shape in which the protruding claw can rotate. And a protrusion or a recess or a step so as to prevent the protrusion claw or the protrusion from moving in the vicinity of the opening of the lateral groove, the structure is simple, but robust and excellent in productivity. You can get things.

Since all the mechanical locking means according to the invention described in claims 5 and 6 can be housed in the outer peripheral wall of the hole, the area of the central hole of the center guide can be reduced. It can be effectively used, and as a result, a thin turntable corresponding to a thinner spindle motor can be obtained.

As described above, the disk clamp mechanism has a simple structure, is robust and has good productivity, and has a high reliability that does not deteriorate the clamping capacity of the disk against changes in the ambient temperature. It is possible to obtain the turntable of the spindle motor.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a turntable showing a first embodiment of the present invention.

FIG. 2 is an enlarged perspective view illustrating a main part shown in FIG.

FIG. 3 is an exploded perspective view showing the assembly procedure of FIG.

FIG. 4 is a sectional view of a turntable showing a second embodiment of the present invention.

5 is an enlarged perspective view illustrating a main part shown in FIG.

6 is a further enlarged perspective view of the main part of FIG.

FIG. 7 is an explanatory diagram illustrating an assembly procedure of FIG.

FIG. 8 is a cross-sectional view of a turntable showing a third embodiment of the present invention.

9 is an exploded perspective view illustrating a main part of FIG. 8 and an assembly procedure.

FIG. 10 is an exploded perspective view illustrating a main part of FIG. 8 and an assembly procedure.

FIG. 11 is a plan view of a main part of a turntable showing a fourth embodiment of the present invention.

FIG. 12 is a perspective view showing in detail an enlarged view of the peripheral structure of the locking means in FIG.

13 is a perspective view showing the structure of a locking portion in FIG. 11 in more detail.

FIG. 14 is a plan view showing a state in which the locking action of FIG. 11 has been executed.

15 is an enlarged cross-sectional view taken along the line CC of FIG.

16 is an explanatory diagram showing a jig used for the locking work described in FIG.

FIG. 17 is an exploded perspective view showing an assembly procedure of the turntable shown in FIG. 11.

18 is a cross-sectional view showing a state in which the turntable of FIG. 11 is assembled to the rotor of the spindle motor.

FIG. 19 is a perspective view showing a back yoke according to a fifth embodiment of the present invention.

20 is a cross-sectional view showing the main parts of the turntable according to FIG.

FIG. 21 is a cross-sectional view showing the main parts of a modification of the turntable according to the fifth embodiment.

[Explanation of symbols]

10 turntable body 11 Center guide 12 holes 12a bottom 12b outer peripheral wall 13 Boss 14 Locking claw 20 back yoke 30 magnets 40 rotor yoke 50 rotor magnet 60 shaft

Claims (11)

[Claims] 1. A spindle motor turntable having an annular magnet with an annular back yoke or an annular single magnet on the bottom surface of an annular hole formed in the center of a center guide, wherein the back yoke or the single unit is provided. A turntable for a spindle motor, wherein the magnet is fixed to the bottom surface of the annular hole by a mechanical locking means provided on the peripheral wall of the hole. 2. The mechanical locking means is a locking claw provided on the outer peripheral wall of the hole and having a spring property for locking the outer peripheral edge of the back yoke or the single magnet. The turntable of the spindle motor described in. 3. The mechanical locking means is a locking claw provided on the inner peripheral wall of the hole and having a spring property for locking the inner peripheral edge of the back yoke or the single magnet. The turntable of the spindle motor described in. 4. The mechanical locking means includes locking claws provided on an outer peripheral wall of the hole for locking an outer peripheral edge of the back yoke or the single magnet, and the back yoke or the single magnet. The turntable for a spindle motor according to claim 1, further comprising a notch portion into which the locking claw is fitted on an outer periphery of the turntable. 5. A plurality of the mechanical locking means are arranged radially outward in a protrusion shape on the outer peripheral edge of the back yoke, and projecting claws formed integrally with the back yoke and the hole portion. A vertical groove portion formed in a concave shape capable of fitting the protruding claw of the back yoke provided on the outer peripheral wall, and the outer peripheral wall from one of the side wall surfaces forming the vertical groove portion along the bottom surface of the hole portion. The lateral groove portion formed by cutting out the projection claw in a substantially arcuate shape capable of rotating, and the projection provided near the opening of the lateral groove part so as to prevent the projection claw from moving. The turntable of the spindle motor described. 6. The mechanical locking means includes a projection part integrally formed on a surface of a projection claw radially outwardly arranged in a plurality of projections on an outer peripheral edge of the back yoke, and the outer periphery. A vertical groove portion that is formed in a concave shape so that the protruding claw of the back yoke provided on the wall can be fitted therein, and the outer peripheral wall along the bottom surface of the hole portion from one of the side walls that form the vertical groove portion. A lateral groove portion formed with a substantially circular arc shape in which the projection claw provided with is movable, and a recess or step provided near the opening of the lateral groove portion so as to prevent the projection portion from moving. The spindle motor turntable according to claim 1. 7. The mechanical locking means according to claim 2, wherein a locking claw having a spring property is provided on an outer peripheral wall of an annular hole formed in the center of the center guide, and (1) An annular back yoke is inserted into the hole, the outer peripheral edge of the back yoke is locked by the locking claw, and an annular magnet is adhered to the upper surface thereof, or (2) an annular back yoke is inserted into the hole. A method of assembling a turntable of a spindle motor, wherein a single magnet is inserted, and the outer peripheral edge of the single magnet is locked by the locking claw. 8. The mechanical locking means according to claim 3, wherein a locking claw having a spring property is provided on the inner peripheral wall of an annular hole formed in the center of the center guide, and (1) An annular back yoke is inserted in the hole, the inner peripheral edge of the back yoke is locked by the locking claw, and the shaft of the spindle motor is press-fitted into the boss formed in the center of the center guide. An annular magnet is adhered to the upper surface of the back yoke, or (2) an annular single magnet is inserted into the hole, and the inner peripheral edge of the single magnet is locked by the locking claws, and the center guide A method of assembling a turntable of a spindle motor, characterized in that the shaft of the spindle motor is press-fitted into a boss portion formed in the central portion of the. 9. The mechanical locking means according to claim 4, wherein a locking claw is provided on an outer peripheral wall of an annular hole formed in the central portion of the center guide, and (1) an annular shape is provided in the hole. Back yoke is inserted, the notch provided on the outer periphery of the annular back yoke is fitted, then the back yoke is rotated and the outer peripheral edge is locked by the locking claw, and the upper surface thereof Or an annular magnet is bonded to the hole, or (2) an annular single magnet is inserted into the hole, and a notch provided on the outer periphery of the single magnet is fitted into the locking claw, and then this A method of assembling a turntable of a spindle motor, wherein a single magnet is rotated and the outer peripheral edge is locked by the locking claw. 10. The mechanical locking means according to claim 5, wherein an outer peripheral wall of an annular hole formed in a central portion of the center guide is provided with a vertical groove portion and a vicinity of the opening portion adjacent to the vertical groove portion. A lateral groove portion having a protrusion is provided on the side wall surface of the groove, and a back yoke having a plurality of protruding claws integrally arranged in the outer peripheral edge is inserted into the hole, and the protruding claws are Fit into the vertical groove portion, then rotate the back yoke in the direction of the lateral groove portion to fit the protruding claw into the lateral groove portion, and lock the protruding claw with the protruding portion provided in the lateral groove portion. A method for assembling a turntable for a spindle motor, characterized by bonding an annular magnet to the upper surface of the yoke. 11. The mechanical locking means according to claim 6, wherein an outer peripheral wall of an annular hole formed in a central portion of the center guide is provided with a vertical groove portion and a vicinity of the opening portion adjacent to the vertical groove portion. Providing a lateral groove with a recess or step on the side wall of the groove,
A plurality of protruding claws integrally arranged on the outer peripheral edge in a protruding shape and a back yoke having a protruding portion on the protruding claw surface are inserted into the holes, and the protruding claws are fitted into the vertical groove portions. Then, the back yoke is rotated in the direction of the lateral groove, and the protrusion is fitted into the lateral groove, and is locked at the recess or step provided in the lateral groove, and is attached to the upper surface of the back yoke. A method of assembling a turntable for a spindle motor, which comprises bonding an annular magnet.